Dutch produce line in skilful fight with English (9)
I believe the answer is:
delftware
'dutch produce' is the definition.
'line in skilful fight with english' is the wordplay.
'line' becomes 'l'.
'in' means one lot of letters goes inside another.
'skilful' becomes 'deft' (I've seen this before).
'fight with' becomes 'war' (warring is a kind of fighting. I am not sure about the 'with' bit.**).
'english' becomes 'e' (abbreviation).
'l' placed inside 'deft' is 'delft'.
'delft'+'war'+'e'='DELFTWARE'
(Other definitions for delftware that I've seen before include "Decorative stuff" , "crockery" , "pottery" .)